U.S. network to detect crop security threats

The National Plant Diagnostic Network (NPDN) is marshaling diverse resources, ranging from sophisticated laboratories to trained, on-farm sentries, to protect the nation's food supply from introduced pests and pathogens.

The mission of NPDN, a linkage of five university hubs across the U.S., including the University of California, Davis, is the rapid and systematic detection of crop threats so state and federal authorities can contain and eradicate them as necessary.

Emerging in the wake of the Sept. 11, 2001 terrorist attack, it is part of the comprehensive network for diagnosis of plant and animal diseases under the Agricultural Bioterrorism Protection Act of 2002. It also generates a valuable national database on pest and disease incidence.

“This is agriculture's response to 9/ll,” he said. “We've seen examples throughout history where introduction of an exotic species has caused major economic and social disruption.”

Foreign plant pathogens or their vectors, such as late blight of potato causing famine in the 1800s in Ireland or glassy-winged sharpshooter spreading Pierce's Disease in California grapes in recent years, occurred naturally, but an enemy could also deliberately introduce them.

“It's not a matter of if but of when,” said Goodell.

Raise awareness

“We want to raise the awareness of those in the field to report new problems. Those might be an unusual behavior of a pathogen, resistance to fungicides, or development in a lower temperature. Anyone who is walking the fields on a day-to-day basis is a first detector.”

Incidence of an introduced disease in crops, he added, would be less dramatic than, say, an outbreak of anthrax in livestock. “But with NPDN, if we found a case in Kern County, another in Tulare County, and then one in Butte County, we would have a state network with a national database to determine whether these are just random events.”

The primary diagnostic laboratory for the western region will be at the California Department of Food and Agriculture in Sacramento, although scientists at UC, Davis also will be involved.

The National Agricultural Pest Information System, an arm of USDA's Animal and Plant Health Inspection Service, at Purdue University is the central archive for data on samples collected through the five diagnostic centers.

Among priority pathogens and pests of concern to the western region are bacterial wilt, broomrape, downy mildew, Pierce's Disease, gypsy moth, fruitfly complex, and soybean rust (a threat to common bean crops in the west).

People in fields

According to Goodell, the key component, aside from the diagnostic centers, is the corps of detectors among crop consultants, pesticide applicators, seedsmen, growers, Extension specialists, and others who spend time in fields and are the first to be aware of irregularities with crops.

He said plans are to begin training in March of first detectors, who could conceivably number in the thousands in California, through UC Cooperative Extension. Other states will have equivalent training programs following NPDN procedures.

Extension specialists will train first detectors in scouting of fields, collection, preparation and submission of samples, and steps to take when unusual pests are observed. First detectors will be required to be certified by NPDN and to complete continuing education courses.

A typical NPDN pathway once an unknown pathogen or pest is collected would begin at a local Extension office. If the sample could not be identified there, it would be referred to a university laboratory. If still unidentified, it would go to a regional laboratory and if necessary on to the national center at Purdue University, where the potential threat and any subsequent action, perhaps containment or eradication, would be evaluated.

“Now we have a central place for California where samples from up and down the state can be used to identify a pattern. Protocols are set up for issuing Section 18 permits to rapidly deal with management of threats of major outbreaks,” Goodell said.

He said an agricultural terrorism event most likely would be aimed at large-acreage, Midwestern grain crops rather than localized, specialty crops in California. “Nevertheless, you can imagine what would happen if a quarantine pest were introduced to a crop like strawberries, for example, and shut down a local economy.”

Responding to a question from the audience on how the NPDN relates to California's fiscally-challenged Cooperative Extension, Goodell said “This is a major national mandate that provides additional evidence of the importance of local UCCE offices at a time when we are defending our budgets.”